This invention relates to a computer controlled system, and in particular to a touch switch for use with a computer controlled system.
It is common in the use of computers for many application programs to make available to the user a series of menus which enable him to make selections of particular functions that he desires the computer to perform. In a typical application involving a menu, a plurality of choices with labels are displayed on the computer monitor. By default, usually one of the choices is highlighted, typically by reverse video. The user can then operate the cursor keys to move the highlighting of the menu items. When the arrives at the choice the desires to make, meaning that that particular menu item is highlighted, the then presses the keyboard enter switch in order to execute the function indicated by the label on the selected choice.
There are many other situations in which the operator, for example, of a machine has available a display which provides the operator with selections to be made. One example is a mailing machine, in which the operator can place the machine in different modes by executing a menu choice from a keyboard in a manner similar to that described above for a personal computer.
Touch screens are also commonly used in the art as a convenient way for a user to make a function selection. In one popular form, a series of electrical or optical switches are built into the front plate of a display. When the menu is displayed, the user merely has to reach up and touch the screen over the function choice that the desires. His finger or any other object that the user may be permitted to use is sensed optically or electrically and its location determined and processed by the computer to enable the desired function to be executed.
The foregoing systems suffer from various disadvantages. The touch screen approach is user-friendly but very expensive. It moreover has the disadvantage that the screen may be soiled by the user's touch which would interfere with the user's ability to view the display. The personal computer approach using a traditional PC keyboard has the disadvantage that the cursor keys are not directly mapped to the particular menu items. In other words, the cursor keys will simply move the highlighted area around the screen in the same way that the screen cursor is moved around, but the user must observe the display to ensure that the proper selection is highlighted before the executes the function by pressing another key on the keyboard. Moreover, for the control of the machines, for example the mailing machine previously allued to, an expensive keyboard of the type traditionally used with personal computers is unnecessary if the object is not to provide alphanumeric text but merely to simplify the task of the user to make menu selections.